As a newcomer to the gym, I often heard the term “plate” thrown around but had no idea what it meant or what it weighed.
I then learned a plate refers to a 45-pound weight plate. For example, “my deadlift one rep personal record is four plates.”
This would mean their deadlift is 405lbs. Because 4 plates on each side = 45lbs x 8 + a standard gym bar of 45lbs equates 405lbs.
Only once I was a seasoned powerlifter did I learn that different types of plates weigh different amounts, which also have other uses for different training outcomes.
Allow me to expand on this.
The Different Types Of Plates In The Gym & What do they weigh?
You may encounter 3 types of plates in your lifting career. All 3 types of plates represent the same weight (45 lbs).
However, they are not really the same weight due to their material and their manufacturing process. They are also used in different circumstances and environments.
Bumper plates are the most common type of plate, often used in big commercial gyms, as they are the most cost-effective due to how they are manufactured.
Bumper plates comprise a metal core and a thick rubber outer layer, making up most of the plate. Bumper plates are also called “Olympic weightlifting plates” as they are prevalent in weightlifting.
This is because weightlifting consists of 3 lifts that end in dropping the bar from shoulder level or above the head. Rubber can absorb this impact of the drop as it simply bounces off the floor, prolonging the life of the bar and causing no damage to the plates themselves.
Speaking from experience, dropping a bar loaded with iron or calibrated plates from shoulder level is not a wise choice. You risk damaging the plates and bar, which can end in a hefty invoice from your gym.
The bumper plate’s weight is often accurate, being within 0.5lb of the advertised weight.
Iron plates are pretty rare these days, often found in old-school gyms. Iron plates gained notoriety in the “golden era” of bodybuilding, with the likes of Arnold and Ronnie Coleman training with strictly iron plates.
They are rarely manufactured these days due to the cost of iron increasing and the cost of plates, in general, rising tremendously.
Iron plates are slightly smaller in diameter and a lot smaller in width than bumper plates. Hence, experienced lifters prefer iron or calibrated plates because they take up less space on the bar, allowing more weight to be loaded.
Iron plates have gained notoriety for being incredibly inaccurate with the weight of the plate itself. For example, no iron weight plate weighs precisely the same: a 45 lb plate can be as little as 40 lbs or as heavy as 50 lbs, depending on how well the plate has been maintained and manufactured.
Calibrated plates or competition plates are true to their name. They are the most weight-accurate plates hence why they are measured in kilograms: a 20 kg plate will be 20kg dead when weighed, thus why they are commonly used in competitions like powerlifting and strongman.
Calibrated plates aren’t very common in commercial gyms: they are more widely found in sport-specific gyms like powerlifting gyms.
Calibrated plates are also vastly more expensive than iron or bumper plates due to their accuracy and precision of being true to their weight.
Frequently Asked Questions
This depends on your training outcome, if you are an average gym goer, then bumper plates are your best bet, they will be closer calibrated than an iron plate and will be more regularly available in a commercial gym.
Iron plates are a novelty that tends to be used more due to their pedigree, so if you got a bodybuilding show, there’s no harm in pumping some iron.
Calibrated plates should be used by athletes that are preparing for a competition in either powerlifting or strongman to represent best how the weights will feel on competition day.
If a powerlifter is to train with uncalibrated plates, they can’t guarantee the weight they are using, which may cause complications for their programming and overall performance.
In my first powerlifting competition, I was utterly unused to how compact calibrated plates felt as the weight distribution was completely different than what I was used to as I trained on bumper plates in my training, I took the initiative after that competition and joined a powerlifting gym.
Yes, that’s correct, however, weight plates come in different weights and sizes. Bumpers and calibrated plates also come in colors too, such as:
45 LB is the most common and notorious, so it’s referred to as “the plate” the other weights would typically be referred to as their weight so, for example:
“I am going to load a plate and a 25 on the bar” This is typical gym lingo, it took me a while at the beginning to understand, but after a few weeks of hearing people use the lingo, it will be second nature.
Another note to add, bumper plates are all one size no matter the weight however, calibrated and iron plates tend to be smaller as the weight lessens, 45 pounds being the biggest plate and 1 lb being the smallest.
The Last Rep
As a seasoned powerlifter and qualified sports scientist, I can see how, on the surface, knowing what the different types of plates weigh and what they are referred to as can seem pointless.
But it’s those athletes like yourself that seek knowledge about every variable of their training that will succeed and achieve their goals efficiently, effectively, and, most importantly, safely.
I’ve seen many athletes in my time as a trainer injure themselves and ignore advice wasting their potential, but the fact that you’ve made it to this page shows you will not be one of those athletes.
Take responsibility for your training and use the proper plates that suit your training outcome.